Systems for transmitting digitized voice frequently utilize a vocoder for analyzing a short frame of speech and for outputting a voice frame containing a number of audio bits as a response. These audio bits are subsequently used in the receiver to reconstruct a replica of the speech. For typical vocoders, the audio bits in each frame have varying levels of importance to audio quality.
Procedures, often referred to as Voice Channel Procedures (VCPs), are used to apply the available overhead to the audio bits in order to insure that the audio bits arrive at the receiver with optimum or adequate audio quality. For example, a typical VCP might divide the overhead such that more error protection is given or applied to the more important audio bits of each frame than is applied to those audio bits of lesser importance. However, conventional VCPs fail to permit sufficient flexibility in providing error protection to different audio bits.